1. Field of the Invention
The invention relates to a method and/or a system and/or a communication network device and/or a communication control element usable in an arrangement for controlling connection parameters for a communication connection, in particular a packet based communication connection. The invention relates particularly to a method and/or a system and/or a communication network device and/or a communication control element usable in an arrangement for dynamically controlling connection parameters wherein connection parameters, network resources, charging information and the like are authorized by a policy control entity of a communication network.
2. Description of the Related Art
In the last years, an increasingly extension of communication networks, i.e. of wire based communication networks, such as the Integrated Services Digital Network (ISDN), or wireless communication networks, such as the cdma2000 (code division multiple access) system, cellular 3rd generation communication networks like the Universal Mobile Telecommunications System (UMTS), the General Packet Radio System (GPRS), or other wireless communication system, such as the Wireless Local Area Network (WLAN), took place all over the world. Various organizations, such as the 3rd Generation Partnership Project (3GPP), the International Telecommunication Union (ITU), 3rd Generation Partnership Project 2 (3GPP2), Internet Engineering Task Force (IETF), and the like are working on standards for telecommunication network and multiple access environments.
In general, the system structure of a communication network is such that a subscriber's user equipment, such as a mobile station, a mobile phone, a fixed phone, a personal computer (PC), a laptop, a personal digital assistant (PDA) or the like, is connected via transceivers and interfaces, such as an air interface, a wired interface or the like, to an access network subsystem. The access network subsystem controls the communication connection to and from the user equipment and is connected via an interface to a corresponding core or backbone network subsystem. The core (or backbone) network subsystem switches the data transmitted via the communication connection to a destination, such as another user equipment, a service provider (server/proxy), or another communication network. It is to be noted that the core network subsystem may be connected to a plurality of access network subsystems. Depending on the used communication network, the actual network structure may vary, as known for those skilled in the art and defined in respective specifications, for example, for UMTS, GSM and the like.
Generally, for properly establishing and handling a communication connection between network elements such as the user equipment and another user terminal, a database, a server, etc., one or more intermediate network elements such as support nodes or service nodes are involved. One or more connection parameters are used for defining connection characteristics. This includes, for example, a packet based data transmission protocol information, such as a PDP (Packet Data Protocol) context information, for example, information about quality of service (QoS) requested or provided, charging-related information, such as a charging class, etc.
In particular in cases where a communication involves two or more networks of different types such as networks using different transmission protocols, e.g. GPRS/UMTS-based networks and IP-based networks, problems may occur in properly establishing the communication connection and setting the connection parameters such that they are optimal for the service in question.
Hitherto, there have been proposed several concepts for achieving a solution for these problems. For example, in the case of a 3GPP based network, such as UMTS/GPRS, the following solutions are proposed.
While in a standard 3GPP system QoS is defined per Access Point Name (APN), in 3GPP Release 5 (see, for example, 3GPP specification TS 23.207, ver5.7.9 (2003-03)), a so-called Policy Decision Function (PDF) is introduced for dynamically authorizing of QoS for IP Multimedia System (IMS) sessions. IMS specific information, Authorization Token and Flow ID(s) are used as binding information when requesting QoS authorization for a PDP context. According to 3GPP Release 5, the PDF (or also Policy Control Function PCF) is described to be implemented together with a Proxy Connection State Control Function (P-CSCF) of the IMS. However, a standardized interface towards the IMS when the PDF is not part of the P-CSCF is not defined in 3GPP Release 5.
Regarding the basic communication between a GGSN (Gateway GPRS Support node) and a PDF, reference is also made to the International patent publication No. WO 02/32165 of the present applicant, which is incorporated by reference.
In 3GPP Release 6 (see, for example, 3GPP specification TR 23.917, ver0.7.1 (2003-02)), it is planned to extend the dynamic authorization to include also streaming services (for example, Packet Switched Streaming Services (PSS)). Furthermore, according to the current understanding of 3GPP Release 6, a stand-alone Policy Decision Function (PDF) with standardized interfaces towards both the GGSN (the so-called Go-interface) and the IMS/PSS (the so-called Gq-interface) are planned.
Thus, it is to be noted that in 3GPP Release 5 and 3GPP Release 6 solutions, a dynamic QoS control for a communication connection is possible for session-based services, and in particular real-time services such as Voice over IP (VoIP) traffic. More generally, PSS streaming service is planned to be added to dynamically authorized services in 3GPP Release 6, in addition to IMS services of 3GPP Release 5.
Another approach for enhancing QoS support for IP services is the usage of so-called service aware core network element, such as a service aware GGSN (saGGSN), or the usage of so-called Intelligent Service Nodes (ISN). The saGGSN and the ISN are service aware products which can provide, for example, specific charging functions. A GGSN provides charging per PDP context whereas service specific charging functions, as one example, can operate on a service flow level. The saGGSN and the ISN are currently defined in respective specifications. A saGGSN allows for the detection of the QoS level at the network edge for selected services. With these enhanced core network elements, QoS can be controlled on a per service access point (sAP) basis or on a service basis within a sAP.